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Stimulating Start-up Investment Through Government-Sponsored Venture Capital: Theory and Chinese Evidence

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Journal of Systems Science & Complexity 2024年第5期37卷 2021-2053页

作者： ni Xuanming ZHENG Tiantian GAO Feng zhao Huimin School of Software and Microelectronics Peking University School of Economics and Management Tsinghua University School of Business Sun Yat-sen University

Government-sponsored venture capital(GVC) has been used to support financially constrained start-ups as an important policy tool in China. Typically, to motivate the social capital to invest in start-ups, GVC provides subsidies for them to bridge the funding gap in the early-stage venture capital market. However, the effect and mechanism of GVC affecting social capital investment have not been clearly studied. In this paper, the authors not only develop a game model to analyze this issue in theory, but conduct an empirical study by analyzing the 14741 records matched by propensity score matching(PSM) of Chinese venture capital market data from 2011 to 2021. The proposed findings are as the follows. Firstly, the subsidies offered by GVC will simultaneously increase the returns and risks of investments in start-ups of social capital with more volatile incentive effect of GVC. The incentive effect of GVC is only effective when the returns resulting from the subsidies outweigh the risks they introduce. In the context of the Chinese venture capital market, the incentive effect of GVC is effective. Secondly, the incentive effect of GVC is more pronounced in high-tech industries, which can be attributed to the signaling effect facilitated by GVC. In this context, the subsidy mainly helps social capital to bear the costs associated with screening potential investments. Thirdly, the incentive effect of GVC is more significant in underdeveloped venture capital markets, which can be explained by the “virtuous cycle” effect, in which GVC plays a pioneering role in establishing a more robust early-stage market trading system. By examining these three points, this study contributes to a better understanding of how GVC can effectively guide social capital investment, especially in the Chinese landscape.

关键词： Government-sponsored venture capital fund incentive effect social capital subsidy venture capital

Effects of Rattling Behavior of K and Cd Atoms along Different Directions in Anisotropic KCdAs on Lattice Thermal Transport and Thermoelectric Properties

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Energy & Environmental Materials 2024年第6期7卷 388-398页

作者： Yue Wang Yinchang zhao Jun ni Zhenhong Dai Department of Physics Yantai UniversityYantai 264005China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China

We employ advanced first principles methodology,merging self-consistent phonon theory and the Boltzmann transport equation,to comprehensively explore the thermal transport and thermoelectric properties of ***,the study accounts for the impact of quartic anharmonicity on phonon group velocities in the pursuit of lattice thermal conductivity and investigates 3ph and 4ph scattering processes on phonon *** various methodologies,including examining atomic vibrational modes and analyzing 3ph and 4ph scattering processes,the article unveils microphysical mechanisms contributing to the lowκL within *** features include significant anisotropy in Cd atoms,pronounced anharmonicity in K atoms,and relative vibrations in non-equivalent As atomic *** atoms,situated between As layers,exhibit rattling modes and strong lattice anharmonicity,contributing to the observed lowκ*** flat bands near the valence band maximum translate into high PF,aligning with ultralowκL for exceptional thermoelectric *** optimal temperature and carrier concentration doping,outstanding ZT values are achieved:4.25(a(b)-axis,p-type,3×10^(19)cm^(−3),500 K),0.90(c-axis,p-type,5×10^(20)cm^(−3),700 K),1.61(a(b)-axis,n-type,2×10^(18)cm^(−3),700 K),and 3.06(c-axis,n-type,9×10^(17)cm^(−3),700 K).

关键词： anharmonic lattice dynamics electron transport characteristics first principles calculation lattice thermal transport octahedron thermoelectric properties

Novel self-assembled porous yolk-shell niO nanospheres with excellent electrochromic performance for smart windows

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Particuology 2024年第1期84卷 72-80页

作者： Baoshun Wang Ya Huang Siming zhao run Li Di Gao Hairong Jiang Rufan Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing100084China

With the rapid development of optoelectronics,electrochromic(EC)materials(ECMs)with the advan-tages of low power consumption,easy viewing,high contrast ratio,etc have attached more and more attention from the fields of smart windows,electronic billboards,emerging wearable and portable electronics,and other next-generation *** oxide(niO)is a promising candidate for high-performance ECMs because of its neutral-colored states and low ***,niO-based ECMs still face the problem of slow switching speed due to their low electrical conductivity and small lattice ***-organic frameworks(MOFs)are promising candidates to fabricate hollow and porous transition metal oxides(TMOs)with high ion transport efficiency,excellent specific capacitance,and electrochemical *** this work,porous yolk-shell niO nanospheres(PYS-niO NSs)were syn-thesized via a solvothermal and subsequent calcination process of ni-MOF,which exhibited outstanding EC *** the large specific surface areas and hollow porous nanostructures were conducive to ionic transport,PYS-niO NSs exhibited a fast coloring/bleaching speed(3.6/3.9 s per one coloring/bleaching cycle)and excellent cycling stability(82%of capacity retention after 3000 cycles).These superior EC properties indicated that the PYS-niO NSs was a promising candidate for high-performance EC *** work provides a new and feasible strategy for the efficient preparation of TMOs ECMs with good EC performance,especially fast switching speed.

关键词： Electrochromic nickel oxide Metal-organic frameworks Hollow structure Smart windows

Recent Research Progress of Paper-Based Supercapacitors Based on Cellulose

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Energy & Environmental Materials 2024年第3期7卷 345-373页

作者： Chuanyin Xiong Tianxu Wang Jing Han zhao Zhang Yonghao ni College of Bioresources Chemical&Materials Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Materials Science and Engineering Tianjin Polytechnic UniversityTianjin 300387China Department of Chemical and Biomedical Engineering The University of MaineOronoMaine 04469USA University of New Brunswick Limerick Pulp&Paper CtrFredericton New Brunswick E3B 5A3Canada

In recent years,paper-based functional materials have received extensive attention in the field of energy storage due to their advantages of rich and adjustable porous network structure and good *** an important energy storage device,paper-based supercapacitors have important application prospects in many fields and have also received extensive attention from researchers in recent *** present,researchers have modified and regulated paper-based materials by different means such as structural design and material composition to enhance their electrochemical storage *** development of paper-based supercapacitors provides an important direction for the development of green and sustainable ***,it is of great significance to summarize the relevant work of paper-based supercapacitors for their rapid development and *** this review,the recent research progress of paper-based supercapacitors based on cellulose was summarized in terms of various cellulose-based composites,preparation skills,and electrochemical ***,some opinions on the problems in the development of this field and the future development trend were *** is hoped that this review can provide valuable references and ideas for the rapid development of paper-based energy storage devices.

关键词： cellulose electrochemical performance flexibility paper-based supercapacitor porous

维普期刊数据库

Durable Design of Superhydrophobic Coatings with TiO_(2)Particles and Al_(2)O_(3)Whiskers for the Enhanced Anti-icing Performance

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Journal of Bionic Engineering 2024年第3期21卷 1360-1374页

作者： Weilan Liu Kunlong Li Yizhou Shen Huanyu zhao Yaru ni Zeyu Cai Lingfeng zhao Zhen Wang Institute of Advanced Materials(IAM) School of Materials Science and EngineeringNanjing Tech UniversityNanjing211816China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China Aviation Industry Aerodynamics Research Institute of China Shenyang110000China

Superhydrophobic coatings with high non-wetting properties are widely applied in anti-icing ***,the micro-nanostructures on the surfaces of superhydrophobic coatings are fragile under external forces,resulting in reduced ***,mechanical strength and durability play a crucial role in the utilization of superhydrophobic *** this study,we employed a two-step spraying method to fabricate superhydrophobic FEVE-based coatings with exceptional mechanical durability,utilizing fluorinated TiO_(2)nanoparticles and fluorinated Al_(2)O_(3)microwhiskers as the *** composite coating exhibited commendable non-wetting properties,displaying a contact angle of 164.84°and a sliding angle of 4.3°.On this basis,the stability of coatings was significantly improved due to the interlocking effect of Al_(2)O_(3)*** 500 tape peeling cycles,500 sandpaper abrasion tests,and 50 kg falling sand impact tests,the coatings retained superhydrophobicity,exhibiting excellent durability and application ***,the ice adhesion strength on the coatings was measured at only 65.4 kPa,while the icing delay time reached 271.8 s at-15℃.In addition,throughout 500 freezing/melting cycles,statistical analysis revealed that the superhydrophobic coatings exhibited a freezing initiation temperature as low as-17.25℃.

关键词： Superhydrophobic coatings Anti-icing Mechanical durability

A modified back analysis method for deep excavation with multi-objective optimization procedure

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1373-1387页

作者： Chenyang zhao Le Chen Pengpeng ni Wenjun Xia Bin Wang State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Guangdong Research Center for Underground Space Exploitation Technology School of Civil EngineeringSun Yat-sen UniversityGuangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Zhuhai519000China Jiangsu Provincial Transportation Engineering Construction Bureau Nanjing210004China

Real-time prediction of excavation-induced displacement of retaining pile during the deep excavation process is crucial for construction *** paper proposes a modified back analysis method with multi-objective optimization procedure,which enables a real-time prediction of horizontal displacement of retaining pile during *** opposed to the traditional stage-by-stage back analysis,time series monitoring data till the current excavation stage are utilized to form a multi-objective ***,the multi-objective particle swarm optimization (MOPSO) algorithm is applied for parameter *** optimized model parameters are immediately adopted to predict the excavation-induced pile deformation in the continuous construction *** achieve efficient parameter optimization and real-time prediction of system behavior,the back propagation neural network (BPNN) is established to substitute the finite element model,which is further implemented together with MOPSO for automatic *** proposed approach is applied in the Taihu tunnel excavation project,where the effectiveness of the method is demonstrated via the comparisons with the site monitoring *** method is reliable with a prediction accuracy of more than 90%.Moreover,different optimization algorithms,including non-dominated sorting genetic algorithm (NSGA-II),Pareto Envelope-based Selection Algorithm II (PESA-II) and MOPSO,are compared,and their influences on the prediction accuracy at different excavation stages are *** results show that MOPSO has the best performance for high dimensional optimization task.

关键词： Multi-objective optimization Back analysis Surrogate model Multi-objective particle swarm optimization(MOPSO) Deep excavation

Decadal prediction skill for Eurasian surface air temperature in CMIP6 models

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Atmospheric and Oceanic Science Letters 2024年第1期17卷 9-13页

作者： Yanyan Huang ni Huang Qianfei zhao Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina Nansen–Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Dalian Meteorological Bureau of Liaoning Province DalianChina

评估CMIP6年代际预测试验对季节平均SAT的预测技巧的结果表明:模式不能有效预测冬季和秋季SAT的年代际变率.IPSL-CM6A-LR和多模式集合平均对于春季SAT展现了预测技巧,其中对于变率的预测技巧好于振幅的结果.基于蒙古和我国华北地区的显... 详细信息

评估CMIP6年代际预测试验对季节平均SAT的预测技巧的结果表明:模式不能有效预测冬季和秋季SAT的年代际变率.IPSL-CM6A-LR和多模式集合平均对于春季SAT展现了预测技巧,其中对于变率的预测技巧好于振幅的结果.基于蒙古和我国华北地区的显著预测技巧,模式对于夏季SAT表现出最佳的预测水平.与外部强迫相比,模式对于SAT的预测技巧可能来自初始化.模式中的一个明显系统性误差值得注意,即模式中冬季SAT的变率可以持续到其他季节,而在观测中其他季节的SAT变化与冬季SAT相对独立.

关键词：欧亚地表温度年代际预测 CMIP6 DCPP

维普期刊数据库

Multi-layer hierarchical cellulose nanofibers/carbon nanotubes/vinasse activated carbon composite materials for supercapacitors and electromagnetic interference shielding

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Nano Research 2024年第3期17卷 904-912页

作者： Tianxu Wang Chuanyin Xiong Yongkang Zhang Bo Wang Qing Xiong Mengjie zhao Yonghao ni College of Bioresources Chemical&Materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China Department of Chemical and biomedical Engineering The University of MaineOronoME 04469USA University of New Brunswick Limerick Pulp&Paper CtrFrederictonNB E3B 5A3Canada

Developing porous self-supporting electrodes with excellent conductivity,good mechanical properties,and high electrochemical activity is crucial for constructing electrode materials with lightweight,ultra-thin,flexible,and high capacitance *** this work,we prepared a cellulose nanofibers(CNFs)/carbon nanotubes(CNTs)/vinasse activated carbon(VAC)(CCV)composite material with a multi-layer hierarchical conductive structure through simple vacuum filtration and *** this composite material,the self-assembly of CNF provides the main skeleton structure of a multi-layer hierarchical *** provides a fast path for the rapid transfer of electrons and is beneficial for the loss of electromagnetic *** provides sufficient double layer *** synergistic effect of the above three endows CCV composite materials with excellent energy storage performance and electromagnetic interference(EMI)shielding *** addition,we endowed the CCV composite with a certain shape and performance by introducing a vitrimer polymer with a dynamic cross-linked network *** summary,thanks to the synergistic effect of various components in the multi-layer hierarchical structure,CCV composite materials exhibit excellent integration performance,especially stable energy storage performance and EMI shielding *** significant properties make CCV composite materials have great application prospects in the fields of energy storage and intelligent EMI shielding.

关键词： self-supporting electrodes multi-layer hierarchical structure supercapacitors electromagnetic interference shielding

Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3047-3062页

作者： Jianhua Yan Xiansen Xing Zhihai Li Weida ni Liuyuan zhao Chun Zhu Yuanyuan He School of Earth Sciences and Engineering Hohai UniversityNanjing210098China POWERCHINA Huadong Engineering Corporation Limited Hangzhou311122China Zhejiang Huadong Construction Corporation Limited Hangzhou310004China The Seventh Geological Brigade of Hubei Geological Bureau Yichang443000China

In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation *** this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable *** study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks *** proposed approach was applied to a granite mine in ***,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit ***,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each ***,a bench face angle was determined commensurate with an acceptable risk level of *** simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.

关键词： Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope